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Filed 001;. 1. 1928 2 Sheets-Sheet 1 May 19, 1931. J. H. WALLACE 1,305,549

RBTRIEVING DEVICE FOR AEROPLANES Filed Oct. 1. 1928 -2 Sheets-She9t 2 Patented May 1 9, 1 931 UNITED STATES PATENT OFFICE JACOB H. WALLACE, OF SAN DIEGO, CALIFORNIA; JULIA M. WALLACE ADMINISTRATRIX OF SAID JACOB H. WALLACE, DECEASED v RETRIEVING DEVICE FOR AEROPLANES Application filed October 1, 1928. Serial No. 309,659.

This invention relates to improvements in devices for retrieving or picking up objects from the ground, by a moving aeroplane.

The objects of the invention is to provide improved equipment for aeroplanes, whereby goods, mail, fuel, supplies, and the like can be picked up from the surface of the ground or water while in flight and traveling at high speeds.

A preferred embodiment of the invention is disclosed in the accompanying drawings in which Figure 1 is a view illustrating the manner in which aload is retrieved.

Figure'2 is a view in cross section of the cable drum and winding mechanism.

Figure 3 is a view in vertical section taken on line 33 of Figure 2.

Figure 4 is a view in side elevation of the cable drum showing the brake mechanism.

Figure 5 is a view in vertical section taken on line 5-5 of Figure 2, showing the cable drum and brake mechanism. I

Figure 6 is a view in end elevation of the cable drum and frame, showing the auxiliary brake, and

Figure 7 is a perspective view of a bucket or container suitable for the goods to be retrieved.

The retrieving or lifting apparatus is mounted within the fuselage or body of the aeroplane and preferably within a compart ment for the purpose. In general the apparatus consists of a drum on which is wound a length of cable which is let out through an opening in the bottom of the aeroplane body, and carries at its end a hook, as illustrated in Figure 1.

The invention, however, provides for more than merely a cable which can be let down and drawn up intothe plane by means of a winding drum,- inasmuch as means must be provided for slacking away on the cable when contact is made with the load, and until the inertia of the load has been overcome and its speed accelerated to that of the plane. This isaccomplished,-as will presently be seen, by means of brake mechanism acting on the cable drum, thereby permitting a certain amount of slippage between the set in from the ends of the longitudinal frame members.

Extending transversely of the frameis a shaft 3'journalled in bearings 4, 4, midway between the ends of the longitudinal frame members 211,20. Centrally of this shaft 3 is a ball bearing assembly on which the cable drum 1 rotates. Thecable drumcomprises a central disc or web 1a having a heavy annular bearing portion 1?) surrounding the ball bearings 5, and a wide outer marginal rim 10 with edge flanges 112. On the rim of the drum is wound a length of cable 6, the end portion of which is shown in Figure I as extending downwardly to the ground and carrying a book 7 .at its end.

Adjacent the disc 1a of the drum is a circular gear plate 8,- having a hub surround ing the shaft 3 between the'right-hand bearing 4 and a radial flange 9, integral with the shaft 3, and forming a side bearing for the drum bearing 5. The plate 8 is made fast to the flange 9 by means of pins 9a, thus the plate and shaft turn together. About the periphery of the plate 8 is an internal gear formed of pins 10a spaced about the edge of the plate and projecting laterally from its outer face, the ends of the teeth being anchored in a fiat ring 11. Offset from the main shaft 3 is a stub shaft 12 journalled in a bearing in the frame, and carrying at its inner end a spur gear 13 meshing with the internal gear 10 of the plate 8. The outer end of the stub shaft ,12 has a tongue 12a to fit the slotted end of a crank handle 14, the corresponding end of the main shaft 3 being similarly be applied to either being imparted direct to the main shaft and in the other instance through the intermediate spur gear 13 and gear plate 8.

Diametrically opposite the spur gear is a spring pawl 15, journalled on a pin 16 supportedin the adjacent frame member 2a. The pawl has a detent on its end adapted to engage the pin teeth 100 on the gear plate 8, to lock the same against rotation in one direction, and also a release lever 15a whereby the pawl may be held out of tooth-engag ing position. A flat spring 17 fixed to a pin 18, anchored in the side frame member 2a, bears at its free end against the short arm of the pawl to hold the same yieldingly in tooth-engaging position.

On the opposite side of the drum disc from the gear plate (left in Figure 2) is located the brake mechanism (Figures 4 and comprising parts as follows: A hub 19, having a. flange 19a at its inner end, occupies the space on the ma n shaft 3 between the lefthand bearing 4 and the ball bearing 5. lntegral with the hub 19 is a brake arm 20, fixed to the main shaft by a set screw 21 in the hub 19. The brake arm extends radially from the main shaft to a point adjacent the internal face of the cable drum and to its outer end is fixed one end of an internally expanding and contracting brake band 22. The brake band preferably consists of a metal ring or band 22a of practically a full circle, having a strip of brake lining 22b su rounding it. One end of the brake band is fastened as by rivets to the end portion of the brake arm which is bent at right angles as at 20a. At the opposite end of the brake band is fixed a bracket 23 consisting or a metal bar bent to form two sections at right angles to each other, one end of the bracket being riveted to the free end of the brake band and the other at a point some distance inwardly therefrom. As thus mounted, one section of the bracket assumes a position parallel with and spaced a short distance from the brake arm 20, and passing from one to the other is the adjusting mechanism, consisting primarily of a rod 24 fixed at one end to the bracket and having a threaded end portion passing at right angles through a threaded boss 25 of the brake arm 20 intermediate its ends. Surrounding the rod between the brake arm and the bracket 23 is a coil spring 26, bearing at one end against the bracket and at the other end against a collared nut 27 threaded on the rod. Also threaded on the rod and bearing against the brake arm is an adjusting nut 28. By turning the nut 28 the rod may be lengthened or shortened, thus increasing or decreasing the frictional contact of the brake band against the cable drum, and similarly by adjusting the spring adjacent nut 27 the action of the spring against the free end of the brake band may be varied. For convenience a gage arm which arm 29 is provided on the brake end of the extends parallel with the threaded rod. This gage arm is suitably graduatedso that the adjustment may be accurately made.

The operation of picking up an object by the use of the device thus described will be understood from the following: As the plane approaches the point where the load is waiting to be picked up, the operator releases the pawl 15 and by means of the crank 14 mounted directly upon the main shaft, unwinds a sufficient length of cable to bring the hook close to the ground, the length being governed by the altitude at which the plane is flying. He then allows the pawl to lock the gear plate against further rotation and removes the crank handle. As the hook engages the load, its weight plus the sudden strain on the cable will cause the drum to turn in a direction to unwind more of the cable, but since the shaft is held against turning by the pawl 15, the unwinding of the drum is resisted by the braking force of the brake. Thus at the instant of contact with the load, the strain on the cable will be the greatest and hence the slippage between the cable drum and the brake band will relieve the sudden strain of a dead weight being lifted, with the result that the cable continues to unwind against the braking force on the drum in direct proportion to the Weight of the load and until the inertia of the load has been overcome and it has acquired the speed of the plane. As soon as the unwinding of the cable has stopped, the crank handle is applied to the stub shaft 12 and the operator now reels in the cable and the load is taken aboard.

The maneuvering of the plane in making contact with the load is clearly illustrated in Figure 1. In order that the load may clear the ground as soon as possible, the plane immediately moves upwardly and the load trails to the rear as it gains speed and altitude.

Up to this point the load has been referred to generally as any object which may be retrieved by a plane in flight. As a preferable arrangement a container is provided for the purpose, consisting of a tubular bucket-like receptacle 30 (Figures 1 and 7), having a bail 30a to be caught by the hook at the end of the cable. The receptacle may be of a flexible material so that it can be partially collapsed while resting on the ground, and extended to full length as it is lifted. Moreover, the receptacle can be provided with wings 31 and a fin 32, the former tending to lift the load as it travels through the air, and the latter to keep the receptacle from twisting.

If desired, an auxiliary hand-operated brake may be employed for use in emergency (Figures 4 and 6). This brake is mounted near one end of the frame 2 and consists of necte 40 velopment and there two uipright links 33, 33, one pivotally conto brackets 34, 34 mounted on each longitudinal side frame member 2a adjacent the flanges 1d, 1d of the cable drum 1. Connected to these links near their lower ends are brake shoes 35, 35 adapted to bear against theouter faces of the drum flanges 1d, 1d. Pivotally connected with the end of one of the links 33 is a cross link 36, and with the other a bell crank lever 37, the longer arm thereof forming the operating handle 37a and the shorter arm 37b being connected with the free end of the cross link 36. By pressing downwardly on the handle 37a the shoes 35 are brought into braking contact with the drum, as clearly appears from Figure 6.

In disclosing the invention I have shown a comparativel simple application of the principles invo ved. However, it is to be understood that the a paratus may be variously modified and ela rated, depending on the particular use to which it is to be put. For instance, motive ower may be utilized for the unwinding and reeling in of the cable and various types of ground rigging may be employed, depending on the character of the load and the nature of the surface from which the load is to be retrieved. These are all matters of experimentation and deore it is to be understood that the invention is not limited to the specific features shown. I c aim as my invention: 1. In a device for the purpose described,

the combination of a frame, a driven shaft journalled in said frame, a cable drum looselyjournalled on said shaft, brake mechanism mounted on said shaft and comprising an expanding and contracting brake band having frictional engagement with the drum, means for adjusting said brake band to exert predetermined frictional resistance to the rotation of said drum on the shaft, and a releasable member for locking said shaft against rotation in one direction.

2. In an apparatus for the purpose described, the combination of a shaft, a cable drum loosely journalled on said shaft, brake mechanism fixed to said shaft and having 59 frictional engagement with said drum and normally acting to contact the same with said shaft, means for adjusting said brake mechanism to permit slippage of said drum when a predetermined load is exerted upon said cable, and means for positively locking the shaft against rotation in one direction.

3. In an apparatus of the character described, the combinationofa rotative shaft, a cable drum journalled to rotate freely on said shaft, a brake-band fixed to said shaft and having frictional contact with said drum whereby the same normally rotates with said shaft and adapted to permit a predetermined relative rotation of said drum when a load as is applied to mid drum through its cable,

and means forlocking said shaft against rotation with said drum during the relative rotation of the latter under said load.

4. In an apparatus for the purpose described, the combination of a rotative shaft, a drum journalled to rotate freely on said shaft and having a cable adapted to be wound thereon, a brake fixed to and rotative with said shaft and having an adjustable band in frictional contact with said drum and adapted to normally connect said drum with said shaft, and to permit relative rotation therebetween under a load suddenly applied through said cable, and means for holding said shaft against rotation with said drum under said load.

5. In an apparatus for the purpose described, the combination of a shaft, means for rotating said shaft, a cable drum loosely from said drum by said shaft rotating means and against rotation during the rotation of said drum undera load applied to said cable in excess of the frictional resistance of said brake mechanism.

6. In an apparatus of the character described, the combination of a rotative. cable drum, a driven shaft, brake mechanism fixed to said shaft and normally acting to frictionally connect said drum to said shaft when there is less than a predetermined load exerted on said cable, but permitting said drum to revolve during the exertion of more than said predetermined load thereon, and means for holding said shaft against rotation under said load.

7. In an apparatus of the character described, the combination of a frame, a shaft journalled in said frame, a cable drum journailed to rot-ate freely on said shaft, brake Sept, 1928. 1

JACOB H. WALLACE, 

